When to Flush Your Water Heater
Here are some signs it’s time to flush your hot water heater:
Discoloured or rusty water – Sediment buildup causes rusty coloured water when small particles enter your water supply. Flushing removes the sediment and rust.
Strange smells – Rotten egg odours or other unpleasant smells indicate bacteria buildup in your tank. Flushing sanitises your tank.
Rumbling or banging noises – Sediment accumulation in the tank bottom causes odd noises as the water heater runs. Flushing quiets these disruptive noises.
Higher energy bills – Sediment buildup reduces heating efficiency, increasing energy usage and costs. A flush water heater runs optimally.
Older system – Water heaters over 4-5 years old benefit from seasonal flushing. Flushing extends the lifespan of aging systems. But if your hot water system is more than 15 years old, you should go for a cylinder replacement.
What You Need To Flush a Water Heater
Gather the following supplies before flushing your water heater:
Garden hose – At least 10 feet to reach a safe drainage area
Bucket
Water heater rinse kit or flushing wand
Adjustable wrench
Screwdriver
Clamp (for hose connection if needed)
Safety Tips
Working with a water heater involves electrical, water, and gas hazards. Keep safety top of mind:
Turn off power to electric water heaters at the breaker before flushing
Shut off the gas valve and pilot light on gas water heaters
Shut off the incoming water valve on the water inlet
Check that all valves/switches are properly closed
Ensure drainage hose reaches an area able to handle large volumes of hot water safely
Use caution when initially opening the drain valve due to hot water release
Allow the tank to fully cool before continuing if unable to drain immediately
Step-by-Step Water Heater Flushing Instructions
Follow these key steps to flush your conventional water heater storage tank:
Turn off the power, water, and gas to the water heater. This may require flipping breakers, shutting water valves, and turning off gas lines depending on your system.
Attach a garden hose to the drain valve near the bottom of the tank. Make sure it can reach a safe drainage area outside like a driveway or yard area.
Place the other end of the hose in a bucket. This catches any initial sediment release. Take caution when first opening the valve as hot water will release.
Fully open the drain valve. Allow water to flow into the bucket first until it runs clean then redirect the hose to your drainage area.
Open the pressure relief valve at the top of the tank. This allows air flow, so the tank drains completely.
Flush the tank for 3-5 minutes once the water runs clear and smooth. This removes loose sediment and freshens the interior tank surface.
Close the drain valve and remove the garden hose. Rinse out the bucket used to catch initial sediment.
Attach a flushing wand or rinse kit to the drain valve. Insert the longer hose fully into the tank opening.
Open the drain valve. Turn on the water for 1-2 minutes, allowing fresh water to spray inside the tank. This further rinses sediment from interior surfaces.
Close the drain valve and remove rinse kit accessories. Replace any insulation or protective metal cover.
Close the pressure relief valve. Turn water and power supply back on to the water heater. For gas systems, reignite the pilot light if needed.
Allow the tank to fully refill and reheat before turning faucets back on in the building. Check for normal operation. Drain and refill the tank completely one more time to rinse away any remaining loose sediment.
Performing Routine Maintenance
Take a few additional steps to keep your water heater running efficiently after flushing:
Drain 5 or so litres from the tank every 3-4 months to remove mineral deposits. Perform mini-flushes in between full flushes.
Inspect anodes regularly if your tank model contains them. Anodes reduce corrosion inside the tank. Replace them as needed.
Monitor your water heater temperature. Maintaining 120°F provides optimal bacteria control without wasting excess energy reheating water.
Insulate hot water pipes to minimise standby heat loss as water flows to fixtures. This improves efficiency.
Know When to Call a Professional
While flushing your water heater is an easy DIY chore, some symptoms indicate professional service is needed:
Leaking tanks – Leaks often mean tank failure requiring full replacement.
Faulty T&P relief valve operation – Improper valve functioning compromises safety.
Inoperable water heaters – If your water heater fails to ignite or drains but won’t refill, call a technician.
Contact Hot Water Solutions Today!
Having hot water heater troubles even after flushing? Our licensed technicians provide repair, maintenance, and installation services across Auckland. As a family-owned business, we pride ourselves on responsive emergency plumbing services combined with affordable routine water heater care.
Use our contact us page to reach us and we will be more than happy to discuss your hot water situation. Or give us a call on 0800 497658.
At Hot Water Solutions all we do is hot water!
